Historical Document · 1948
TICOM DF-120: Report on the M-209 (German cryptanalysis)
German wartime technical report on the M-209 and its solution, translated for TICOM.
Historical Document · 1948
German wartime technical report on the M-209 and its solution, translated for TICOM.
"REPORT ON CIPHER Attention appearing sixth in line is from the 10 to ( bottom the number of 33 the actual number obvious that 12 1948 July l,33" is the apparent 100 33 of - page positions the OF MESSAGES IN of 0 55«4.00 to etc 13* The This step positions., nunber discrepancy be ) between and division in From doubled 0 chart the the in the 10 is AS-23, AS-14 2 AS -70, A3-76-C 3 AS -80, AS U AS-90, 5 AS 6-7 CSAT 3-9 LSIC 10 CSC- 11 CEO 12 ASA/Eui-ope 13 ASA 24 ASA/School, 15 AS -93 16 AS -94 17-18 AS -80 19-20 AS -70 21-25 file file file -S3 file AS-95 file -96 ID /Pacific Officer's Training the text two AMERIC figure in calls 33 the for operations account copies: pa AS~10, THE it is E.C* - 1 OF statement textual 25 Distribution: DEPTH M-209 x doubling being SOLUTION DEVICE celled figure THE n Copy No0 ^ TOP SECRET DP-120 TICOlUDoc, ON THE SOLUTION AMERICAN The 794., attached German srtkanf of iraand of the German a Europe to T1CCM camp in TICOH Doc. by Using Ti?o conform to scribod here cation U.S. at at in f MESSAGES IN DEVICE H-209 in with Army quite statistical other May June the Signal Intelligence 7/VI)» As Service, and were a Austria, of they been of Different similar the in this Absolute Indicators") these been is taken Agency to methods found usege. be interesting in order While employed to Setting in the because end the to have AS-1A AS-76-C AS-80, AS-83 file AS-90, AS-95 file file file 3 4 can -96 8-9 LSIC .10 CSGID CBO ASA/'Enropa ASA/Pacific ASA/School, AS -93 AS -94 AS -30 AS -70 Officer's Training Division 16 17-18 19-20 file TOP found ASA/ was W-l the techniques Hagelin self of (as of related clear - AS-70, 6-7 were through translation No. 25 AS-23, the informa its SECRET done (13-209) text des- type explanatory. probable problems. AS-10, AS of 1947» 2 21-25 result forwarded 1 5 THE Agency of pages: copies a EC Distribution: 15 OF ■ Copy 12 13 DEPTH 1948 Translated: 11 01 t: CSGAS-14.-TIC0M 23 IC Losung K-2C9* Austria, has has die Intelligence Security presentation of Agency (OKH/GdNa/ln "Determination standard the Array liberty Messages the aber reports Military LSIC 2795, are the Glasenbach, Considerable problems OF CIPHER Security fffrMtw-nlntftMnn one by Army "Bericht is in of an This buried One is title: achn received 3o /AS-14-T 2794 REPORT tion 53A8/T0PSEC No*. *• 17 appli- TOP REPORT ON THE SECRET SOLUTION lop Iiitrpdaet Today have the in our task section is of such machine basis of such linguistic which is valid that reason here to Eethod of operation follow ay presentation* a mention day, to the First of ail a machine of the Eagelin but is title M-209, Sweden* 36, in The and few machine follov/s the same the basis important for linguistic of ciphered with of of a the the 6 keywhselo in the in to the of THE known same purely lb* by type or as 0 BC-38« already just remark it is a ^ill matter letter only whose to the lengths the 26 26, wheel to the produced well-known explain after of 25, all that 101, the 23, the EC- this message in here encipheraerit product are \:as built appears you under so sequence end essentially, a is for and for of machine the like (because of The corresponds not sol~ machine, aspects isf It rae substitution^ should It let each the Americans the on ii Th^ &-209o construction I i*e0f of necessary the which linguistic linguistic itself AII~1 I basic vork (possible principle^ that machine, the the setting absolutely as principle; number the purely machine i3 either to Section the is us substitution This OF Machine Cipher internal the which of the much substitution,. same substitutions. about survey reconstruction up as solution) different short tfce cryptographic this polyalphabotic repetition 850 of American to so machine belongs detail jr.eans only by the taken type, known a of myself words you while is you of DEPTH M-209 DEVICE exclusively solution) restrict therefore on 2a messages, the to giving restricted utioa for of Soction in accomplished being vork I IN Reaarks General : KSSSAGES CIPHER MBR2CAR A„ OF is by is en a 4C:.S, lengths 21, 3.9, and letters me pri the alphabet are represented; on the 25 wheel *ltn is 1 TOP SECRET missing; on the 23 wheel TOP WW, 19 Y, Z" are wheel letters from setting rather "T, q missing; W, X, rtIi to Zn are of messages of One position means at cf a choice stitutions phabet rate, be effective were tnis day— -a is such the clear the help the of course against each of given the from the solution these is That in one of one the the beginning at the end the this fact in permit me Americans of the more occurred message place few in recognisable message, another a of mostly I will TOP the in go are a solution general type will two AABCD in each That sub- standard al- At any which of machine the groups if will appear one the on the superimposes determine, message shew more The the use are but into more detail concerning some of theater indicator order, also this clearly African same of with at first which — same arrangement the SECRET at substitution 5-letter EPGXI, the different other 1942 cases substitutions can remarks* December through I b3 sliderulej) position the to reciprocal. say, one the effective setting to for sc-em 26 the internal reverse the on all certain indicator is the messages messages, letters Q are two in possible given text remarks messages any clear utilizes my at the and external possible. of These when the wheel definite (Compare and 17 and one missing; would us possible* of letters the only similarity knows way which different internal the gives alphabet 26 are change this However, one 3lide, :ial ZK alphabetical is position* same in other* if at At which on daily message and war* of the are slid with of The message, in I, substitutions, noi of by the X, and however, a however, machine The K, a enciphered because any our How With about apparent text First, versed. 26 messages, position. the at missing,, in0 "V, missing; ones linguistic two of know enciphered and in not are different been do Z" position of come have we each T, wheel circumstance, breaking individual out 21 V, hopeless. that tho U, solution possibility on SECRET groups repeated times the re- meaning TOP SECRET <Jt first internal new traffic were solved strength the from and Italy with from is otherwise, The from the no division corps use do?m of used ex- of matter system entire the into the and solved depth later in army which w*s invasion army mainly messages had been from the in messages Italy, Eng~ never- which, Evaluation, to built up* Since and front Western * the of picture clear rather a invasion, and waiting hints valuable gave Thus, Sicily, messages, practice of which appeared* this read could we machine, kneran system, strip Africa, invasion of to valid for a regulations, the indicator key 6 the depth would is not appear at all0 the definite supposed always is for Including, wheels, this fortunately principally and to, in in th but in a like with on setting rcessr.ges is the According message, machine of worked daily* to the invasion external the and of setting 7?sr was used this messages question currently being changed as of a mainly the of are message theater beginning internal it, long composition beginning The and was the by that, as it entry widely by supplanted Anglo-American read were theless, the the it Here land* so from from also and currently messages linguistically were then the is, analytically* found 1943, was strip, DRSAL or M-94 as setting May and April in When machine that Since • the letters, messages two The them* with succeeded 6C2 of messages long ceptiorially 1943 January in appeared groups, indicator depth, in messages first The indicators,, the of encipherment battalions* of key and, group to done, changed, be for, tactical Sometimes, area Messages however, even it* wo be noted that from us in Gerraan Traffic Signal Analysis Intelligence and corresponds ion" TOP SECRET practice closely Kvalur- TOP Bo Solution of Following cuss ion recall the this of the what I position in clear Messages said text at of at Depths introductory methods one la SECRET of the the two the survey actual outset: messages same I if depth, position like linguistic viz., in should of I proceed solution. know then, the to the vrith second If clear the to you text of is very dis- will at help message a please any our slide, easy to re- constructo Here in bet shoul 1. Piguro (See the I two on left writes machine the at the two circular can be slid at alphabet, cipher letters time* against Our position, exploited the at example, each must If at the the appear. Therefore, figure Let we same 0 is in This method, have attempted of is a set the down at second is clear know the all in at very to with appear of a fragment which in the and the of follows. thsse clear- entire fact one can be message message and, be message, clear time alpha tfhich of can put the than the message in hand strips This position bothersome simplification us other message, leas with are of relationship positions any right as position the machine setting nor 3lide. letters the other furnishes this at and this the text more each by of internal suspected text actually however, the we word clear is to iMediately effective be the came wheel nothing next if the vve operated to are set Thu3, manner: word position type then, and corresponding suspected the machine slide number—can position, sought* then, a following how corresponding other which just enciphering, slides, the passing shows the unrolled * each alphabet in in In hand alphabets one explain alphabets0 substitution —for to illustration The ) reciprocal the cipher like text wasting0 (See 2.) us assume that at all TOP the positions of the first SECRET message the clear TOP tert letter aZn apoears and SECRET see which clear text letters correspond to it in Th3se second mm for nAw« n3w. and responding as a As you the heading, will ve the by means see, alphabet, her write but, letters by no letters of does rhonever oao alphabetical the this has a alphabet have to be complete progression* vith which we had begun* done for all the column, one can obtain The completed strips letters of the are tin g X&JSp?. arart the a word THREBC) separation clear text met or be letter expected built fragments top the •jexts text up of occur* of the nessagc* at Further, to other a upper turn the glance it ha3 procedure, alphabet is the appear* obtained and that after the in strips duplicate since the suspected wordo shown to is, figure of our to try this in the other and to coliems, one under around and we you can in can try the find count the clear text, the lines one occurs to message the other same SECRET * trial at use any the 9 clear of a word strips we work letters have 5.n in of letters corresponding probable above coin- a sane all the where position the all Then fron alternately not as the trial below by that message try, tried the and message TOP line above dosm the order is practical write a be and method: second 5 can hits trial actually very in you wZtt In you position the word be If alternately t^y this 3„) slice, If text* appear message, exact the farther up will second following the in message the help whether been message in further up after thereby to see the vrith made (Compare , have can of text building we the second the in have reverse in cidence, then, will We and obtain build is before clear Norj, to 2-3trip step-wise0 and down, belor;, and The to the d TOP Strip and practical bsscd In is same pit a time ship U - D a?.phabets inner a of outer spond to a the 9 are above slide, at inner slide, type and of wheel one upperlying we now (See figure must put we is it a very tedious raeahanicallyo by Ofu. have in POKORN*) which D so that other, being sure A which text this same is facto at the of that appears the strip* carries the first type draw f i3, With clear outer inner slide must Thus slide, we across have again in upon is turn the a?>ove the would the ttZrf corre- in tight, exactly the which fixed have, towards has relation- fastened corresponding wheel set which 9o Q which Opposite letter m slides is only alphabets only you nDtt. message,, slugs Q, message above Z cipher two Now ir3t the type Ths bottom. the - devise direction. letter of We Z "P*. letters the letters interval similar the relationship cipher letters, the the two that two tort lias against other UZ* to wQff - each message, has a U ?/rite the "Zn 4») the clear to clear always between only under position only (invented the cipher our doing between exploit second this writer of interval letter then, method messages, the the 77e the the letters is a that of strip each to the a long depth, tfUw So written that f,Zw there in a 9n# for principles: reciprocals) so letter the for (algebraic). against are way cipher order, sign direction. slide the is look interval corresponds the such the of reverse we messages wminus the in of not especially following HZ" interval so solution as interval (this an ease hand, job, the reversed we the on a the with If by time-wasting very i3 writing SECRET to the right -> in order to (N.C.O., the obtain or American the Under alphabet officer, Hagelin Alfred Section TOP beginning of with POKORN In 7/71 was of the a clear text cryptanalyst OKH« SECRET See TICOM letters of attached 1-175.) the to TOP •Z" column. cess of the each actual line 2c to appearing bac] clear to the reached where, both messages 0 One can before* If If is Tbe progress, naroe iteolf messages all the Snglish Firot the i new word good try, the latter we OTlte, ceediog position. seeking out, text bir-raphs build up, way garble with we —in for oust ^hich at the to the combines seeking (See figure that the in follows one of 5 into the and one pro- initial letter 6)c so-called c yield, first we line, the next and displaced all red one cone would r/rite black third upon not the be a the one the 3ana second which letter, correct * then -7- TOP SECRET at another (See figure 7*) the the nZw two same on in positions strip, right, for past possible if correct and under corre- one, first clear English and of sue- each the strips. all its these fourth, possible special massages, a both time, devise Alongside the probable 0 continuation find text of thing the both method the give further of next strip in third the%K> to appears a we alphabet the to at of little letters able in is break-in following purpose this positions and a move to in na?r place up trial still messages Do massage* the strip, last, position a construction a nZ* build Frequency out this we begin is that a the obtain point both to renew seek For and try there and second so to the we in ends Bigraph At So but and try alternating desired, can either, begln0 RD as word way, nature the the case what a abbreviations* both the below, this could Then one in in its far succeed, alphabet, from letter not occura as successful at of epondjUig apparatus and column0 often guess has words we the alphabets "Zff and is, which all extent, continued reveals letters each this not bigraphs of the and, that or the It does strips making be then that that in above without pointc of tert. cannot words certain Frequencies* te;ct as a writing Blgraphic JJow of Thus, SECRET we so there then on. is bigraph. In no If TOP or/; has erlbtd found the Text With certain quickly which Offset a must this agreement istako at this It way have two that an message set ar>y for the cipher of in the building however, of Hon, up proceeds that place to the message, the the at upper right, onec this then as des- with would appear the third all the letters of assumed the have "A", alphabet 0 strip that now the the we must Since in to similar in is very 8C) there in loner one, again in is the However, first through "B", *Cn, SECRET it position the etc,, <zas th»l«Mr above, the a the a figure *D* etc0 used aessages, text 0 is be to -8- TOP is there (See the then corresponded carry for two parallel appear position a must there case, have which atthod clear correspond to of beginning, the to stood cipher messages respect "F*, case divergent of would then, become one is same must in such the test, tha must arbitarily both case appear position, stereotyped our messages cipher after message, the in a attaining the position the of in a text0 and could a soma not of when such clear position, alphabet Xs i3 -set this nDn In messages so off message, the it Then If next the groups point the of or on added, first at If foliating farther by o At o two breaking-off -set that fiassages^ the possibility and groups Mpsages* reconstructing upper if off cipher text, two another depth, ceases of mistakenly appears in letters text continuing still both tert omission clear in or 0 in been omitted assume letter ste&d tha is first the the dosage of the at in one lower further messages that, method wAn in originally Often, messages us of agree different was l^t there the except simple provisions position solution letter Place or completely tert, the One (garble) be by solution completely text for continuation, above* 3u very SECRET off- upper in above the since in- sane method one always SECRET TOP gets the rest of of the haa letters the 26 been which alphabets, rows. In sent, According to or in of at tho first position of on to one gets writing which from garble) text of over to the we see that quite two in the In the text tried again to until tai3 one the the jumps system same in third at can texts « be It begin dorm to how but this the a cipher assumed the garble up exactly tro lines is WQW the a trouble table only clear text (transmission of it clear just from jumps the different instead further So, nZw have the jump, letter we we but or a up line position, one message, set that the interval often,, oneself garble in in forgotten. lower out the double trying hare so writo found most or seek is a was saves we to be by upper Naturally, at nZB occurs case, arises must message and order garbled of the 9o) the first fifth TOP the In this the occur a ca^e of which the of from "0" and onp etc* a suspected through message one is must corresponds upper message of that, connection upper position, the first, message position in in easily as lower position the employed can direction figure letter occurs as the only Taroc (See following: in stops that, example text similar the much our clear further* letter as only in m^itten method? text "Zw always other position this double been has text upper immediately the one separation parallels text , clear the will question the Not just similar in in in a one already The and the of For correct found, by such have line* is one, clear rows* have one* two works letter 26 doan, message by alphabet either alphabets. the the sending after noticeable Offset A which the line 4o of into we correct -set correct the another original the alphabets made which off tho them one an down tho bring lower experience trial in example, the the it column-wise our in then folio* j ftith SECRET message the that a offset second offset by consider to dees letter method the error one the clear not appear corresponding we obtain, TOP by alphabetical of two, so one the can SECRET continuation, second, use fourth, this method a kind sixth, for of a etc., theta grid. Furthermore, letters also, with etand&dependoat thereby obtaining a an on offset each second other, square \ which one must text* interlocked, the but that this out Furthermore, od ■* needs can garble or are the The x When complex offset of this first against extended at will After clear text, for offsets and time-wasting, so one or short one every step therefore clear desired the find crust we rows 676 the one* of works 3 , more 4, 59 quickly manner, any two since trouble only , up a with to only the fragment the point help where of of clear our either slide, a appears,, Double other Letter case until to be later, except agree you, to in the Indicator discussed, one that is? when for the doubled I and groups indicator of the method. in the one be into out these can understandable two insert must in a is which the messages few Afferent short 9 messages are words of technique in available order In letter0 enciphering the Group to make concern- the o ten letters letters in wheels. They must be positions of (XI) questio position two offset step, come of without obtained eighth they tested is meaning two key an indicators the Americans the not following ing last new there which the a too strip further Depth How in be build 5o depth to which system with by one In becomes with step lines alia in lines surely text 26 faturally etcc, and be test 26 x 26 can within (of be the the the effective third to indicator denote is (the are the scope first cipher 0 The group) chosen groups area six the group) the by wheels0 serves or the to ollowing ftora basic the The the man, double encipher SECRET meaning* net in third setting radio -10- TOP f cryptosystem letters indicate arbitarily of have of which to the Th<s the six key but of course letter in the this basic first position TOP ^nd is also to enciphered 12 which out the come six key chosen times of » In this message does 21 not in Only if the doubled is other sayf above, which initial G E„ forward thereby, letter the if in you are of the two set the machine depth and vr?vTj messages a letter, is, one depth if we omit the of wXn of genuine the F, since the letter does not appear letter nBw *ix key in the is in of the offset from A to C9 we in the case of an offset from A to D, three could appear because TOP one in letter this had in "Z" the except is by A the aitf sliding depth* give B D of That letters the as letters would be SECRET M F the and Q A will move arrived at and we obtain case, with have to letters, struck the the double omit two etcc The out C second So, connection. to H alphabet* massage an considered can, gave this of be we wheels message Thus, position R case must letter setting along on0 for QAYCWGLEPSZRo the point double will In one agree nkn therefore first on groups messages initial farther letters machine circumstances the the the the letter the decipheredo out.? them are point first H of of indicator double one of D therefore, at letter this B be is letters position times, fi the messages setting from or twelve R the double message letter usable starting setting certain the each "A" double six initial one obtain real the strickened in the can This first the letter which alphabet, initial in be with of be man* the letter the under other, the that exact "B^o letters, & in then give The and in and setting then must encipherraent thea then example encipherment step, the B— each encipher messages messages the would messages radio setting appear, these is settings and one it the double wheel, letter«~for the Now, message two if proceed 23 two against then The the have by this the deciphered on one messages to L we with might therefore Now the the and basic enciphering be appear wheel, for to the ily encipherment BZDXHMPQTAS the arbiter r;ith wheels* Example R be SECRET depth (of the in TOP of positions c If the this Let we vculd. Then obtain the is us of the the out), Q not the with £ messages A V C G E of case, that following two and letters) assume encipherment settings thrown doubled SECRET our then in the aeries two we encipherments do not get encipherment of letters i R any of tie beQAVCWGSEPSZ. would be (W and S follows: had to be the same messages double in depths letter low RBDHFQ (if the X T initial had will thrown the thase first 'sliding two two the settings positions* In two probability tion, initial of becomes messages this against elimination smaller now and of have case, each the little naturally, other letters, xialler very 0 which no depth can be is illuminating has to be the be only in It greater to be namely, that "A" BWDXHTFQTAS. would as at done distance found that by the at the same the two doubled posi~ \J\J$ m letters are 0 separated from each Criteria for Trigraph Differences other Depths 1 What has just ing plain lar indicator messages text in from depth could sent of in the not at setting course, with not in between the the of covers depth* come but the to are us the most important ^ut very many from messages machine correct on 0 cipher cipher texts, o sent For a Often of texts, with TOP the this 0 the by large the -1 2 similar the and can almost be of of a with not the were c was messages can, their (vertical definite length, en- was message by simi- genuine addressee such quite recover* mistake recognized similar SECRET are which real doublets for messages text then Linguistically appearance or the encipherment back, number methods stations, same reason lesseges a of field with query encipherment account two 10) first message, solved appearance graphs) all, the the be which in figure succession decipher again external in discussed messages groups, ciphered twice •ado been (S** with di~ intervals »$ J'j.ar TOP SECRET t give doing that, not possible the correspond M-209 messages of intervals are letters cipher the has been employed exactly the same to letters text clear inf fact the above, as other opposite with -«only the that each In notc or depth in messagesjjj^fr of pair a whether to which sought been has criterion a are these whether advance in decide to apart. hours several or one is usually time therefore, and explained already as between intervals intercept as clue a us could the notf or depth in massages is it however, 0.''ten, the while times, tactical signs. solved From of will a percentage the From these corresponding interval The to weight appears lower message, sum is then since raultipled It investigated,. positions, we have and looked the lower message,, the clear and cipher table is by was in the and 100 and by each position For this reason text by twice the 100 in order to has TOP no by the 3um twice— the meaning. of once different The in which weights the SECRET number the aign final to apply a of of upper the result the each as upper the get us finds themc positions relationship investigated the in for now One divided twice up Indicates messages, cipher up adds which Zahlentripelo two multiplied divided prepared possible every for which the 100 a frequency the of tri- text clear definite product frequencies the „ occurrence triple in being their of the to equal is other each differences as well over ppear two that probability the since arose which (Zahlentripel) of cipher negative the to each to trigraphs these product the from simply up built values occurrences, their graphs of with weighted was number triple The depth* in messages in intervals of corresr>ono found differences The determined* were other intervals text clear the and flZ") letter separator the account into 300 the letters 10,000 (taking counted were trigraphs text clear frequent most of out Africa, from and positions once intervals then gives in for us a TOP , oint of departure depth or not* probable* /een doing this, account 0 been able in to Other 50,000 has shown owe speak can can messages^ depend on the a meseages values against count ii-ake the that (Streuungea) things short whether 4.0,000 scattering on and of 50,000 depth, either and nevertheless, are or depth more with make numbers Of be taken distortion of the to ily now, in we in be- in into picture, have, rather in course, must up particular investigated possibility* coincidences considerable results, being in long general, messages.. Criteria Other 2o under and These especially telling Experience Values 40,000 for SECRET criteria by which depth can be The doublet frequency used about determined are more of an external nature a0 texts whan a of messages at these 6 and 8 ralue here suspicion only means Do in follow With was not of is case each other, for* example, Length and Different English the frequency similar doublet clear clear The etc0 TT, doublets between of thoir in text are This depth. one clear elpfcor also there two when SS, BE, as by two In signifies only occur can when offset are which 3%c doublet A 0 of text expected 2*$* the same that all only occur therefore, messages doublets this length we are one in that wrong the same u.Vth and Solution have aald TOP of and a Encipher encipher the one differences, the I and defiling time trigraph Difficulties After for valid is texts clear text, cipher our is doublets basic the in Different our letter however, b^ sent Doublets* separator in percent is of depth, in since letters word positions criterion text, Rumber same time text time in Messages to you for Depth up then; to StCRET a is messages Here point in Timet both correctly* starting shown ment ment we always and obtain, the that by depth* » now you could get the it TOP impression affair* all that But based of difficulties There sent of to the t*o number and of the All on trigraph a unmistakable enough the success, was was to a very In conclusion date pair o? by There a pointed towards time after break-ins, (See red worked frequent a words in order whole from a day to time of even in we a of in are methods show to lent you you 1944 Italy* a- what which The 51,000 parallel on 170 figure 11) strips, there was length encipherment* three (See the to December the The position, letter se 0 were two figure 11) but reconstruct the internal setting of the message, without any dragging liat 15 7 preparing simple 0 KOMA depth. underline like from calculation quite furthermore, demonstrate dated was a individual should solution likewise gave I was which, the trill massages favourable., depth which which teletype different, avialable in in in examples, cases short We simple overcome 1944 therefore, messages of recent differences letters machine* of December doublets Within of has case messages criteria, yet 16 chosen description. often the machine solutions messages one was us to of purposely genuine well pair solution have upon themselves notrier I the SECRET had through made ourselves* there The were short not red t position tain also there at be It break-in leading an first conditions, narase second as the unsuccessful., proper it in aid waa last we an was, was right also more succeeded not the A the led do than breaking break-in suitable endo was built digraphic not to which to in at be first therefore, dictionary nothing could accidento After backwards a line A in keep with position for although arranged a the we had — SECRET cer- beginning should come was a frequency, from at our in ^ith new Ths front of disposal backwards through PIEU)* under the frequency dragging word at there alphabetically on could, digraphic -15- TOP and frequency digraphic nothing, to further » So, words, that the and other TOP red pieces With possible* been have hardly by this ogni of even of real beginning made recognizable of petition beginning a , quency 8. part of then ends with success from message the of beginning the a a Another •j appears; letters the thus Braes-fl« fre- digraphic a making ex- cases had even word is our in or, have letter the give then beginning The begins) They ■essage. and middle, (message only no have can you naturally, one message the end "-sage", message a of BGWS MSG words the the of sentence * the in somewhere aessage the by in begin messages the have of middle the end the at WZ" or "X" by nulls likewise and forbidden, often possibility, be can attempted Americans the course, of are, beginnings Stereotyped eneipherment which complications the essage the words infrequent and names proper using been not had then, to up fur admit will One strips, our of aid the reed easily were soiled the that After which, message the of parts 1 of setting internal the ease? relative *ith reconstructed be could machine now and immediately apart fell also SECRET used <* 4 filling 10 given nonsense only somewhere abbreviations PARBM, real the letters in the CMa. beginning r.he at will at sages mesemge the at of the CLB, CR XXX, end After begins middle PD, and principally are message, either inclose / Further take Americans can in account of and completely are great the reconstruction in abbreviations, many the of an the invent unmethodical unknown already text very tha difficult. is there itege of garbl our main But the source of always most a sometimes unpleasant entry— are not greater, thing written ■*16«* TOP SECRET is sometimes that out now anymore smeller often but even are TOP sent as when, the as doubled in to this solution experience, coae to letters: can and, ths 1 ie aaj aessage, you often be very to that, added desired SECRET add 2 is many bb; is personal difficult. a 3 little Then bit of cc5....0tf is names infrequent you and hare "fingertip success,. -17« TOP to SECRET jj. have And then words, much feeling" in patience order TOP AM 1? TYPE RECIPROCAL SECRET WHEEL ALPHABET s C leor Cipher gTij aopqrstuvwxyz isyxwvutsrqponmlkjihgfedcba Fisura TOP 1* SECRET SECRET TOP MESSAGES IN BREAK-IN I. MSG. MSG. 1 B B B B E B F z A B C A A A A A A A z i B c i z A B c u I J E L M N 0 P A B C D A B C N 0 P A B C i MSG. 8S3G. z, 2 1 2 V J r V 1 ■ M • z Mm D * • i • • • • : D • • Q • • 0 • • M Q » 0 0 ♦ . z J z I I HI R I B Hi K I E HIR C q E A N E I R d A S F rI s e| r R j £ ff I J I D Z M G Z T s I 0 B Z i w 01 I q B K| f W K J f I C T K I Q\ U H LI I B Figure TOP B ? SECRET z TOP I E3SJ jgg FREAK- I N I SECRET JP.SE II. I R E 2 J * ° Is B E T • 1 «•# j i v T R z T F z C I 1 B z t I 0 B I !M 1 1 G R J I C a 9 R E 1 R ! f J a K ? B z T 7 Z R Z a u E I • 1 i C i i z A 1 ! K X | ft ■ * if H W 1 A 6 I X i It 7 i B 1 * • - * ' 0 I C ! 1 • Q j 3 1 1 1 '* ° 0 I 0 1 qtjib ggydd feyib ax&uli O ' ft o . KG 0 :2E32 . B. 1 BIOS Figur e TOP ^ SECRET TOP STRIP SECRET WRITING FXPIAKATIOK use. 1 t ISO. 2 1 (A tf 2 1 I CLEAR s MSG. c b 1 ■